diff mbox

mmc: dw_mmc: fix dw_mci_get_cd

Message ID 1389780469-32633-1-git-send-email-zhangfei.gao@linaro.org (mailing list archive)
State New, archived
Headers show

Commit Message

Zhangfei Gao Jan. 15, 2014, 10:07 a.m. UTC
Introduced from commit bf626e5550f24aec24975a0e85ad8e572ca76a6b
CDETECT is ignored since negated return value of mmc_gpio_get_cd(mmc)
can not be checked by IS_ERR_VALUE.
Add spin_lock_bh(&host->lock) for atomic accessing DW_MMC_CARD_PRESENT,
otherwise sd detect may occasionally fail.

Signed-off-by: Zhangfei Gao <zhangfei.gao@linaro.org>
Reported-by: Kevin Hilman <khilman@linaro.org>
Reviewed-by: Sachin Kamat <sachin.kamat@linaro.org>
Tested-by: Sachin Kamat <sachin.kamat@linaro.org>
---
 drivers/mmc/host/dw_mmc.c |    9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

Comments

Seungwon Jeon Jan. 15, 2014, 11:58 a.m. UTC | #1
On Wed, January 15, 2014, Zhangfei Gao wrote:
> Introduced from commit bf626e5550f24aec24975a0e85ad8e572ca76a6b
> CDETECT is ignored since negated return value of mmc_gpio_get_cd(mmc)
> can not be checked by IS_ERR_VALUE.
> Add spin_lock_bh(&host->lock) for atomic accessing DW_MMC_CARD_PRESENT,
> otherwise sd detect may occasionally fail.
> 
> Signed-off-by: Zhangfei Gao <zhangfei.gao@linaro.org>
> Reported-by: Kevin Hilman <khilman@linaro.org>
> Reviewed-by: Sachin Kamat <sachin.kamat@linaro.org>
> Tested-by: Sachin Kamat <sachin.kamat@linaro.org>
> ---
>  drivers/mmc/host/dw_mmc.c |    9 ++++++---
>  1 file changed, 6 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
> index a776f24f4311..9ded62c8225e 100644
> --- a/drivers/mmc/host/dw_mmc.c
> +++ b/drivers/mmc/host/dw_mmc.c
> @@ -1033,7 +1033,8 @@ static int dw_mci_get_cd(struct mmc_host *mmc)
>  	int present;
>  	struct dw_mci_slot *slot = mmc_priv(mmc);
>  	struct dw_mci_board *brd = slot->host->pdata;
> -	int gpio_cd = !mmc_gpio_get_cd(mmc);
> +	struct dw_mci *host = slot->host;
> +	int gpio_cd = mmc_gpio_get_cd(mmc);
> 
>  	/* Use platform get_cd function, else try onboard card detect */
>  	if (brd->quirks & DW_MCI_QUIRK_BROKEN_CARD_DETECTION)
> @@ -1041,11 +1042,12 @@ static int dw_mci_get_cd(struct mmc_host *mmc)
>  	else if (brd->get_cd)
>  		present = !brd->get_cd(slot->id);
>  	else if (!IS_ERR_VALUE(gpio_cd))
> -		present = !!gpio_cd;
> +		present = !gpio_cd;
!!gpio_cd or gpio_cd is correct, isn't it?

Thanks,
Seungwon Jeon

>  	else
>  		present = (mci_readl(slot->host, CDETECT) & (1 << slot->id))
>  			== 0 ? 1 : 0;
> 
> +	spin_lock_bh(&host->lock);
>  	if (present) {
>  		set_bit(DW_MMC_CARD_PRESENT, &slot->flags);
>  		dev_dbg(&mmc->class_dev, "card is present\n");
> @@ -1053,6 +1055,7 @@ static int dw_mci_get_cd(struct mmc_host *mmc)
>  		clear_bit(DW_MMC_CARD_PRESENT, &slot->flags);
>  		dev_dbg(&mmc->class_dev, "card is not present\n");
>  	}
> +	spin_unlock_bh(&host->lock);
> 
>  	return present;
>  }
> @@ -2081,7 +2084,7 @@ static int dw_mci_of_get_wp_gpio(struct device *dev, u8 slot)
>  	return gpio;
>  }
> 
> -/* find the cd gpio for a given slot; or -1 if none specified */
> +/* find the cd gpio for a given slot */
>  static void dw_mci_of_get_cd_gpio(struct device *dev, u8 slot,
>  					struct mmc_host *mmc)
>  {
> --
> 1.7.9.5
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-mmc" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
Zhangfei Gao Jan. 15, 2014, 12:10 p.m. UTC | #2
On 01/15/2014 07:58 PM, Seungwon Jeon wrote:
> On Wed, January 15, 2014, Zhangfei Gao wrote:
>> Introduced from commit bf626e5550f24aec24975a0e85ad8e572ca76a6b
>> CDETECT is ignored since negated return value of mmc_gpio_get_cd(mmc)
>> can not be checked by IS_ERR_VALUE.
>> Add spin_lock_bh(&host->lock) for atomic accessing DW_MMC_CARD_PRESENT,
>> otherwise sd detect may occasionally fail.
>>
>> Signed-off-by: Zhangfei Gao <zhangfei.gao@linaro.org>
>> Reported-by: Kevin Hilman <khilman@linaro.org>
>> Reviewed-by: Sachin Kamat <sachin.kamat@linaro.org>
>> Tested-by: Sachin Kamat <sachin.kamat@linaro.org>
>> ---
>>   drivers/mmc/host/dw_mmc.c |    9 ++++++---
>>   1 file changed, 6 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
>> index a776f24f4311..9ded62c8225e 100644
>> --- a/drivers/mmc/host/dw_mmc.c
>> +++ b/drivers/mmc/host/dw_mmc.c
>> @@ -1033,7 +1033,8 @@ static int dw_mci_get_cd(struct mmc_host *mmc)
>>   	int present;
>>   	struct dw_mci_slot *slot = mmc_priv(mmc);
>>   	struct dw_mci_board *brd = slot->host->pdata;
>> -	int gpio_cd = !mmc_gpio_get_cd(mmc);
>> +	struct dw_mci *host = slot->host;
>> +	int gpio_cd = mmc_gpio_get_cd(mmc);
>>
>>   	/* Use platform get_cd function, else try onboard card detect */
>>   	if (brd->quirks & DW_MCI_QUIRK_BROKEN_CARD_DETECTION)
>> @@ -1041,11 +1042,12 @@ static int dw_mci_get_cd(struct mmc_host *mmc)
>>   	else if (brd->get_cd)
>>   		present = !brd->get_cd(slot->id);
>>   	else if (!IS_ERR_VALUE(gpio_cd))
>> -		present = !!gpio_cd;
>> +		present = !gpio_cd;
> !!gpio_cd or gpio_cd is correct, isn't it?
>

No, mmc_gpio_get_cd(mmc) has to revert.
!!gpio_cd is used before since gpio_cd = !mmc_gpio_get_cd(mmc) is used
before.

Thanks
Seungwon Jeon Jan. 15, 2014, 12:26 p.m. UTC | #3
On Wed, January 15, 2014, Zhangfei Gao wrote:
> On 01/15/2014 07:58 PM, Seungwon Jeon wrote:
> > On Wed, January 15, 2014, Zhangfei Gao wrote:
> >> Introduced from commit bf626e5550f24aec24975a0e85ad8e572ca76a6b
> >> CDETECT is ignored since negated return value of mmc_gpio_get_cd(mmc)
> >> can not be checked by IS_ERR_VALUE.
> >> Add spin_lock_bh(&host->lock) for atomic accessing DW_MMC_CARD_PRESENT,
> >> otherwise sd detect may occasionally fail.
> >>
> >> Signed-off-by: Zhangfei Gao <zhangfei.gao@linaro.org>
> >> Reported-by: Kevin Hilman <khilman@linaro.org>
> >> Reviewed-by: Sachin Kamat <sachin.kamat@linaro.org>
> >> Tested-by: Sachin Kamat <sachin.kamat@linaro.org>
> >> ---
> >>   drivers/mmc/host/dw_mmc.c |    9 ++++++---
> >>   1 file changed, 6 insertions(+), 3 deletions(-)
> >>
> >> diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
> >> index a776f24f4311..9ded62c8225e 100644
> >> --- a/drivers/mmc/host/dw_mmc.c
> >> +++ b/drivers/mmc/host/dw_mmc.c
> >> @@ -1033,7 +1033,8 @@ static int dw_mci_get_cd(struct mmc_host *mmc)
> >>   	int present;
> >>   	struct dw_mci_slot *slot = mmc_priv(mmc);
> >>   	struct dw_mci_board *brd = slot->host->pdata;
> >> -	int gpio_cd = !mmc_gpio_get_cd(mmc);
> >> +	struct dw_mci *host = slot->host;
> >> +	int gpio_cd = mmc_gpio_get_cd(mmc);
> >>
> >>   	/* Use platform get_cd function, else try onboard card detect */
> >>   	if (brd->quirks & DW_MCI_QUIRK_BROKEN_CARD_DETECTION)
> >> @@ -1041,11 +1042,12 @@ static int dw_mci_get_cd(struct mmc_host *mmc)
> >>   	else if (brd->get_cd)
> >>   		present = !brd->get_cd(slot->id);
> >>   	else if (!IS_ERR_VALUE(gpio_cd))
> >> -		present = !!gpio_cd;
> >> +		present = !gpio_cd;
> > !!gpio_cd or gpio_cd is correct, isn't it?
> >
> 
> No, mmc_gpio_get_cd(mmc) has to revert.
I'm missing something?
If card is detected, mmc_gpio_get_cd() returns non-zero, right?
I guess gpio_cd should be kept.

> !!gpio_cd is used before since gpio_cd = !mmc_gpio_get_cd(mmc) is used
> before.
> 
> Thanks
> --
> To unsubscribe from this list: send the line "unsubscribe linux-mmc" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
diff mbox

Patch

diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
index a776f24f4311..9ded62c8225e 100644
--- a/drivers/mmc/host/dw_mmc.c
+++ b/drivers/mmc/host/dw_mmc.c
@@ -1033,7 +1033,8 @@  static int dw_mci_get_cd(struct mmc_host *mmc)
 	int present;
 	struct dw_mci_slot *slot = mmc_priv(mmc);
 	struct dw_mci_board *brd = slot->host->pdata;
-	int gpio_cd = !mmc_gpio_get_cd(mmc);
+	struct dw_mci *host = slot->host;
+	int gpio_cd = mmc_gpio_get_cd(mmc);
 
 	/* Use platform get_cd function, else try onboard card detect */
 	if (brd->quirks & DW_MCI_QUIRK_BROKEN_CARD_DETECTION)
@@ -1041,11 +1042,12 @@  static int dw_mci_get_cd(struct mmc_host *mmc)
 	else if (brd->get_cd)
 		present = !brd->get_cd(slot->id);
 	else if (!IS_ERR_VALUE(gpio_cd))
-		present = !!gpio_cd;
+		present = !gpio_cd;
 	else
 		present = (mci_readl(slot->host, CDETECT) & (1 << slot->id))
 			== 0 ? 1 : 0;
 
+	spin_lock_bh(&host->lock);
 	if (present) {
 		set_bit(DW_MMC_CARD_PRESENT, &slot->flags);
 		dev_dbg(&mmc->class_dev, "card is present\n");
@@ -1053,6 +1055,7 @@  static int dw_mci_get_cd(struct mmc_host *mmc)
 		clear_bit(DW_MMC_CARD_PRESENT, &slot->flags);
 		dev_dbg(&mmc->class_dev, "card is not present\n");
 	}
+	spin_unlock_bh(&host->lock);
 
 	return present;
 }
@@ -2081,7 +2084,7 @@  static int dw_mci_of_get_wp_gpio(struct device *dev, u8 slot)
 	return gpio;
 }
 
-/* find the cd gpio for a given slot; or -1 if none specified */
+/* find the cd gpio for a given slot */
 static void dw_mci_of_get_cd_gpio(struct device *dev, u8 slot,
 					struct mmc_host *mmc)
 {